de Carvalho Aroldo P, Pereira Eliane Mara Cesário
Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brazil.
J Pediatr (Rio J). 2006 Jul;82(3 Suppl):S15-24. doi: 10.2223/JPED.1491. Epub 2006 Jun 16.
The use of whole-cell pertussis vaccine has led to a significant decline in incidence of the disease among children. This change in the epidemiological profile led to an increased number of cases among teenagers and adults, as a result of loss of immunity to the disease or vaccine after approximately 10 years. An increased number of cases was also observed among non-immunized or partially immunized infants. Licensure of the DTP vaccine against diphtheria, tetanus, and acellular pertussis formulated specifically for patients over 10 years of age (Tdap) suggests the possibility of controlling pertussis in the most affected age groups over the past few years.
Data were collected from MEDLINE. The research was limited to the period between January 1995 and January 2006.
In some countries there are two Tdap vaccines licensed for patients over 10 years of age. One of them contains five immunogenic components of Bordetella pertussis (pertussis toxin, filamentous hemagglutinin, fimbriae 2 and 3, and pertactin), and the other contains three components (pertactin, filamentous hemagglutinin, and inactivated pertussis toxin), the latter being the only one licensed in Brazil up to now. Although the composition of the two vaccines differs, studies show that they have similar effectiveness and immunogenicity. Some authors, however, emphasize that it is difficult to make a precise assessment of the immunological response to the vaccine and its duration. Several countries currently recommend the use of Tdap vaccine for adolescents. Canada has extended the target population up to 54 years of age. The guideline is that this group should receive one dose of the vaccine to reinforce the basic immunization scheme. This is based on study results that show that the vaccine-induced immunity lasts for around 6 to 12 years. Assessments of the economic impact of routine use of the vaccine in adolescents showed a positive cost-benefit ratio. Results of the epidemiological impact depend on the quality of diagnosis so that data reflect the reality of the disease.
Although some questions remain to be clarified, the literature indicates the possibility of solving the "reappearance" of whooping cough (pertussis) with the use of Tdap vaccine. Perhaps the strategy of using a second booster dose in adolescence to replace the double diphtheria and tetanus vaccine should be adopted immediately.
全细胞百日咳疫苗的使用已使儿童疾病发病率显著下降。这种流行病学特征的变化导致青少年和成人病例数增加，原因是大约10年后对该疾病或疫苗的免疫力丧失。在未免疫或部分免疫的婴儿中也观察到病例数增加。专门为10岁以上患者配制的白喉、破伤风和无细胞百日咳联合疫苗（Tdap）的获批表明，在过去几年中控制最易感染年龄组的百日咳具有可能性。
数据收集自MEDLINE。研究限于1995年1月至2006年1月期间。
在一些国家，有两种针对10岁以上患者获批的Tdap疫苗。其中一种含有百日咳博德特氏菌的五种免疫原性成分（百日咳毒素、丝状血凝素、2型和3型菌毛以及百日咳黏附素），另一种含有三种成分（百日咳黏附素、丝状血凝素和灭活百日咳毒素），后者是巴西目前唯一获批的一种。尽管两种疫苗的成分不同，但研究表明它们具有相似的有效性和免疫原性。然而，一些作者强调，很难对疫苗的免疫反应及其持续时间进行精确评估。目前几个国家建议青少年使用Tdap疫苗。加拿大已将目标人群扩大到54岁。指导原则是该组应接种一剂疫苗以加强基础免疫方案。这是基于研究结果表明疫苗诱导的免疫力可持续约6至12年。对青少年常规使用该疫苗的经济影响评估显示成本效益比为正。流行病学影响的结果取决于诊断质量，以便数据反映疾病的实际情况。
尽管仍有一些问题有待澄清，但文献表明使用Tdap疫苗有可能解决百日咳“再现”的问题。或许应立即采用在青少年期使用第二剂加强疫苗来替代双价白喉和破伤风疫苗的策略。
